5.2.1: Lattice enthalpy Flashcards
Define lattice enthalpy
Formation of 1 mole of ionic lattice from
gaseous ions under standard conditions
What does a more exothermic lattice enthalpy mean?
More exothermic = more stronger ionic
bonds
Why is it not possible to measure lattice enthalpy
directly?
It is not possible to form 1 mole of ionic solid from its gaseous ions
Define enthalpy change of solution
Enthalpy change that takes place when 1
mole of a solute is completely dissolved
in water under standard conditions
Define enthalpy change of hydration
The enthalpy change that takes place
when dissolving one mole of gaseous
ions in water
What are the factors that impact the size of lattice
enthalpy?
● Size of ions involved
● Charges on the ions
● Ionic bond strength
Which ions have more negative lattice enthalpy
values? smaller / larger ions? Why?
Smaller ions because they can get closer
hence more stronger attraction
Describe hydration
When a ionic lattice is broken the ions become part of the solution
Positive ions get attracted towards slightly negative oxygen and negative ions get attracted towards slightly positive hydrogen
What are the factors that impact the magnitude of
the enthalpy of hydration?
● Size of the ion
● Charge on the ions
